ThE killing of takeaway driver Simon San by a group of teenagers in Lochend is one of the saddest stories on which I have had to report.

Simon’s parents came to Edinburgh to build a better life for their family. Instead he was killed, aged 40, as he went peacefully about his work. The jailing of his killer John Reid and Reid’s friend Michael Roberts has clearly done nothing to stop their violent offending. Both are now back behind bars after committing further offences.

Their story does raise questions about the effectiveness of rehabilitation in prison - at least for some of the most persistent young offenders.

Their case - and that of the teenager arrested for another offence just 40 minutes after leaving the dock - also highlights the havock which a small hardcore of young offenders cause in some of our communities.

The problem here is a vicious circle, not just of re-offending, but of dented confidence in the police and courts. That’s not the fault of the police who are doing their job in catching them. The problem is when the courts are a revolving door that spits them straight back out. With the worst serial offenders, the courts are often too reluctant to lock them up - and refuse them bail - in order to protect the rest of society.